Words by Julia Mellor, Founder of The Sool Company 

If you have ever been to Korean barbecue or found yourself binge-watching the latest Korean drama, you have likely come across soju.  Korea’s most iconic alcoholic spirit has been enjoying plenty of growth and attention in recent years, but arguably soju is as misunderstood as it is popular.  Although ubiquitously recognized by its green bottle packaging, the category of soju is far more complex and diverse than its global image would have you believe.  

What is soju? 

The word Soju comes from two Sino-Korean characters, ‘So – to burn’ and ‘Ju – alcohol’, so literally speaking, soju is a distilled spirit.  Traditionally, soju was distilled from a fermented alcohol made of rice, water, and a wild fermentation starter called ‘Nuruk’.   

Nuruk is a host of wild yeast, enzymes and bacteria that are responsible for converting rice to fermentable sugars and, subsequently, alcohol.  With many rice spirits also cultivated in other parts of Asia, nuruk is one of the fundamental distinctions of traditional soju.   

The base alcohol resulting from this fermentation can also be enjoyed in two other categories of Korean alcohol called ‘Makgeolli’, a cloudy rice wine,  and ‘Yakju or Cheongju’, a golden clear rice wine.  These are also enjoying a seismic resurgence of popularity in Korea, with over a hundred new breweries opening in the last 5 years.  They are best enjoyed unpasteurized, which unfortunately makes export to long distances almost impossible. Yet now, the first generation of breweries outside of Korea are producing makgeolli in the US, UK, and Singapore, just to name a few.  

Table strength vs. spirit strength 

An important distinction of soju that differentiates it from other categories of spirits is the alcohol content.  Distilled spirits are naturally high-proof, usually between 30 – 45% ABV or higher.   Yet the soju most international drinkers are familiar with is significantly lower than that standard, with some sojus tapping out as low as 16%.   

There is a reason for that.  Soju is consumed socially over food, in shots, in quantities comparable to wine.  As drinking trends have changed over time, the alcohol content of soju has been reduced lower and lower, allowing consumers to drink more and drink longer.    

And so we have the emergence of two subcategories, what we like to call ‘Table Strength’ and ‘Spirit Strength’ soju.  Table strength soju can range from 16 – 25%, while spirit strength usually begins from 30% and above.  Generally speaking, table-strength soju matches well for dining settings, while spirit-strength can be enjoyed neat or in cocktails.  

Flavoured soju vs. traditional soju 

The popularity of soju globally in recent years is quite different from the soju enjoyed in Korea.  Flavored soju such as peach, lychee and even yoghurt abounds in the international market, with customers drinking it more like a cocktail or RTD.  Although these flavored sojus have attempted market penetration in Korea in the past, they never really took off.  

One of the reasons flavored soju doesn’t enjoy the same popularity in Korea, is because they are simply too sweet.  Soju is always drunk with food, and is present at almost every dinner table.  Korean cuisine boasts rich flavors from spicy and salty to umami and aromatic, so the flavored soju just doesn’t pair well.  In contrast, soju globally is enjoyed in diverse settings away from a Korean dining table, and so it is approached differently.  

Alternative grains and processes  

Although rice is the most representative grain for high-quality soju, other traditional recipes use alternative grains.  Wheat soju, for example, has a long history of being developed in the Andong region, with records dating back to the 1540s.    

Over the course of history, wheat soju gave way to rice in terms of popularity, and now, only a handful of distilleries use these techniques.  

 One such distillery, Jinmaek Soju in Andong, produces an organic grain-to-glass soju that redefines what ‘Traditional’ can mean for the category, inspiring others to embrace modernity while keeping Korea’s distilling culture alive. 

Another emerging category of soju that echoes this philosophy is oak-aged soju.  Soju is not traditionally aged in vessels that can impart additional flavors.  In fact, Korean clay pots known as ‘Hangari’ or ‘Ongi’ were the aging vessel of choice, due to their porous nature, allowing for smooth oxygen transfer. These pots are also used for other fermented pastes and sauces and are an integral part of Korea’s rich fermentation culture.  

That being said, we have recently seen a rise in high-quality soju being aged in oak barrels.  These spirits can be colloquially called ‘rice whiskey’, and while the jury is still out on the accuracy of that term, it shows the growing development of soju as a diverse and complex spirit category.   

From toasted rice to bourbon barrels, there is no shortage of innovation and experimentation in the Korean soju industry. 

The future of soju 

In short, soju is booming in Korea, but perhaps not the soju you might be familiar with.  Although flavored and classic green bottle soju will always have its place and find popularity, there will soon be a coming of age for high-quality Korean soju in the global market.  As the quality of ingredients, skill and experience improves, distilleries will continue to push the boundaries of tradition and modernity, which can only mean we are on the cusp of an exciting era of discovery for Korean alcohol.  

Julia Mellor is the founder of The Sool Company, a resource for traditional Korean alcohol. Her company is based in Seoul and the Netherlands, specializing in Korean alcohol brewing education, tourism, export and international market creation. Mellor is a professional consultant for international commercial brewing, her clients being the first to open ‘makgeolli’ breweries in the US, UK, and Singapore. She’s the first international specialist in Korean alcohol and is both passionate and experienced in successfully bringing Korean sool to global markets. 

This article first came out in our “Sip the Spirit of Asia” issue.